A conventional display device, for instance a display device employing liquid crystal, is provided with a light guiding plate at the opposing surface of a display surface of a liquid crystal display for guiding light to a liquid crystal panel. On an upright surface of the light guiding plate, there is provided a light source such as a line light source, and a reflective member for gathering light from the light source into the upright surface of the light guiding plate and being provided as covering the above-mentioned light source. Between the liquid crystal panel and light guiding plate, there are provided optical sheets, such as a diffusing sheet, for having homogeneous irradiation of the liquid crystal display by diffusing light from the light source. In order to control horizontal movements of the optical sheet, there is provided a ridge which supports the light source, the reflective member and optical sheets on a frame. (For example, see Japanese Unexamined Patent Publication No. 121816/2003).
In addition, there is provided a ridge on the frame, and in order to support the light guiding plate, a part of the upright surface of the light guiding plate is provided as contacting the ridge on the frame. Then, the interval of the light guiding plate and retaining member at the ridge of the frame is narrower than the interval of an end of the reflective member and light guiding plate. (For example, see Japanese Unexamined Patent Publication No. 126523/2001.)
In the above-mentioned conventional technique of Japanese Unexamined Patent Publication No. 121816/2003, the ridge located at the frame controls the movements of the optical sheets, and there is no disclosure nor indication with respect to supporting the light guiding plate through a ridge. When the ridge is located on the frame for supporting the light guiding plate as shown in Japanese Unexamined Patent Publication No. 126523/2001, there has been a problem of occurrence of a display defect such as uneven luminance caused by a scratch of the upright surface of the light guiding plate through contacting the end of the reflective member to the upright surface of the light guiding plate. The present invention is provided in view of solving above-mentioned problems, and objects are to improve withstand mechanical-shock property, control occurrence of a display defect such as uneven luminance and improve quality of display device.